抄録
(1) The shapes of the erythrocytes of vertebrates are in general represented. by the Cassinian oval, the expression (x2+y2+a2) 2-4a2x2=c4; in the case of biconcave discoidal erythrocytes, (x2+y2+z2+a2) 2-4a2 (x2+z2)=where √2a>c>a; in the case of elliptical erythrocytes under the microscope, the projective shape is represented by (x2+y2+a2) 2-4a2x2=c4, where c≤√2a.
(2) The lemniscate is a very close approximation to the shape of a bicon cave discoidal erythrocyte.
(3) The erythrocyte of a vertebrate changes its shape phylogenetically to the direction of increasing the ratio a/c in the Cassinian oval.
(4) The relation between the years since vertebrates have been generated on the earth and the ratio a/c in the Cassinian oval is nearly linear.
